1. Field
The invention relates to a method for cutting mainly a long work using a single-wire type wire saw, and an improved single-wire type wire saw for realizing such method.
2. Related Art
A single-wire type wire saw holds a linear-shaped wire between grooved guide rollers and presses a work against the wire while traveling, thereby cutting the work. Normally, the work is machined and fed at a specific position to the traveling wire by a machining/feeding device. In the cutting step, the wire supporting direction of the grooved guide roller relative to the wire must be always opposed to the work machining/feeding direction the work machining/feeding direction in order to prevent the wire from slipping-off from the grooved guide rollers, the guide grooves of the grooved guide rollers from being unsymmetrically worn, and the traveling wire from meandering.
For example, in WO2008/001816, in a single-wire type wire saw, according to the change of a work cutting direction, a pair of grooved rollers are rotated about the axis of the wire together with a roller-supporting cutting arm to shift the paired grooved rollers supporting direction relative to the wire, whereby the whole rigidity supporting direction of the paired grooved rollers relative to the wire is opposed to the work machining/feeding direction.
According to the technology of WO2008/001816, the roller-supporting cutting arm is disposed in a direction perpendicular to the roller axis of the paired grooved rollers, namely, on the extension line of the work machining/feeding direction. Thus, the length of the work capable of cutting is restricted by the length of the roller-supporting cutting arm. This restriction can be solved by extending the length of the arm. However, in this solution, when the required support rigidity of a mechanical element is secured, the size of the cutting apparatus must be increased, which is not practical.